1. Field of the Invention
The present invention relates to a building structure which has a whole shape formed by connecting unit spaces each having a polygonal-prism shape at least horizontally and includes a hexagonal frame incorporated as a structural member.
2. Description of the Related Art
In general, a conventional building structure has a Rahmen frame formed by connecting straight pillars and horizontal beams into a three-dimensional grid shape, and occasionally, has a frame formed by connecting triangles or hexagons as unit grids.
Particularly, a structure formed by connecting hexagonal frames into a honeycomb shape is long known to be strong and solid. As the hexagonal-frame structure, there are some examples (Patent Documents 1 to 3) in which hexagonal frames are connected in a horizontal plane to form a honeycomb structure while a vertical connection is made by straight pillars. However, the structures according to Patent Documents 1 to 3 have no honeycomb structure in a vertical plane, though having a honeycomb structure in a horizontal plane.
The honeycomb structure has an advantage in that forces applied to a building from various directions can be easily converted into axial forces of beams or pillars. Some structural analyses verify that if given an equal horizontal load, a building having a honeycomb structure in a vertical plane produces weaker deformation and bending-moment stresses than a building having a common Rahmen frame does.
On the other hand, a trussed structure formed by connecting triangular frames is more frequently employed for a dome frame according to Patent Document 4 than for a tube frame.
Herein, Patent Documents 1, 2, 3 and 4 are Japanese Patent Laid-Open Publication No. 5-112984, Japanese Patent Laid-Open Publication No. 5-112987, Japanese Patent Laid-Open Publication No. 9-60301 and Japanese Patent Laid-Open Publication No. 2000-110243, respectively.
Taking the above into account, a building having a honeycomb structure in a vertical plane is expected to have a high stability and an excellent earthquake proof.
In terms of the whole shape of a building, a high-rise or super high-rise building is generally relatively simple because its whole shape extending in the vertical directions requires an excellent earthquake proof or a great wind resistance.
In contrast, low-rise and medium-rise (e.g., two to eight-story) buildings vary in whole shape and some are practically constructed. For example, there is a building having a complex, delicately-uneven contour in plan view, or a building having diverse contours for each story layer.